P3383Left atrial appendage and left atrial morphology is associated with cryptogenic stroke

Abstract

Abstract Background Stroke causes a high burden of morbidity and mortality worldwide. Approximately 30% of stroke cases remain cryptogenic (CS), of which one third is due to occult atrial fibrillation (AF) with left atrial appendage (LAA) being the most frequent thrombus source. Hence, aim of our study was to assess if LAA morphological parameters analysed by computed tomography angiography (CTA) are associated with CS. Methods and materials In 184 patients (Table 1), 82 CS patients and 102 controls (age median 62 (52,2–72), 40.2% females), matched for BMI, a CTA was performed, and LAA morphology evaluated retrospectively. LAA morphology was classified into 5 types (Figure 1): Cactus, Cauliflower, Chicken-wing, Windsock and the new “Seahorse” with a distinctive tip angulation of ≤90° and 2 bends (Z-shape). Further measurements included: LAA tip angulation (≤90°, 91–110°, >110°), LAA lobe number, LAA ostium size (length) and angulation, left atrium wall thickness (LAWT). Results LAA and left atrium (LA) parameters associated with CS on multivariable analysis after adjusting for CHA2DS2-VASc score were: Chicken-wing type (OR 2.15; 95% CI: 1.01–4.56, p=0.046), a greater lobe number (OR 2.01; 95% CI: 1.52–2.64, p<0.001), a greater middle and mean LAWT (respectively, OR 2.13; 95% CI: 1.49–3.05, p<0.001, OR 2.64; 95% CI: 1.63–4.29, p<0.001), a larger (length, OR 1.08; 95% CI: 1.0–1.16, p=0.039) and a less bent LAA ostium (OR 1.02; 95% CI: 1.01–1.03, p=0.006). In contrast, a sharp-angled LAA tip (≤90°) was protective from CS (OR 0.43; 95% CI: 0.23–0.83, p=0.012) on multivariable analysis. Table1. Clinical patient characteristics CS (n=82) Non-stroke (n=102) p value Females 21 (25.6%) 53 (52%) p<0.001 Age, y 66.5 (57–73) 57.5 (50–70) 0.001 BMI, kg/m2 25.6 (23.9–28.2) 26 (23.3–30.1) 0.320 CHA2DS2-VASc score 2 (1–3) 2 (1–3) 0.387 AF (paroxysmal/permanent) 0 4 0.071 Hypertension 68 (82.9%) 54 (56.3%) p<0.001 Diabetes mellitus, type 2 16 (19.8%) 11 (11.5%) 0.145 Values are given in median ± IQR. AF, atrial fibrillation; BMI, body mass index. LAA and LA morphology in CTA. Conclusion In CS, a Chicken-wing LAA, a greater number of lobes and a thicker LA wall are independently associated with CS while a sharp LAA tip (≤90°) mostly seen in Seahorse type LAA is protective. Such “high-risk” LAA and LA morphology could help to select CS patients benefiting from extended rhythm-monitoring to detect an occult AF, however, further prospective studies are needed to confirm this hypothesis.